Stabilized compositions of conductive polymers and partially fluorinated acid polymers

ABSTRACT

There is provided an electrically conductive polymer composition. The composition includes an electrically conductive polymer and a partially-fluorinated acid polymer. At least 50% of acid protons on the partially-fluorinated acid polymer are replaced with cations. The cations can be inorganic cations, organic cations, and combinations thereof.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority from U.S. provisional application Ser.No. 60/817,954, dated Jun. 30, 2006, which is incorporated by referenceherein.

BACKGROUND INFORMATION

1. Field of the Disclosure

This disclosure relates in general to electrically conductive polymercompositions, and their uses in organic electronic devices.

2. Description of the Related Art

Organic electronic devices define a category of products that include anactive layer. Such devices convert electrical energy into radiation,detect signals through electronic processes, convert radiation intoelectrical energy, or include one or more organic semiconductor layers.

Organic light-emitting diodes (OLEDs) are organic electronic devicescomprising an organic layer capable of electroluminescence. OLEDs canhave the following configuration:

-   -   anode/buffer layer/EL material/cathode        and may include additional option layers, materials or        compositions. The anode is typically any material that is        transparent and has the ability to inject holes into the EL        material, such as, for example, indium/tin oxide (ITO). The        anode is optionally supported on a glass or plastic substrate.        EL materials include fluorescent compounds, fluorescent and        phosphorescent metal complexes, conjugated polymers, and        combinations and mixtures thereof. The cathode is typically any        material (such as, e.g., Ca or Ba) that has the ability to        inject electrons into the EL material. The buffer layer is        typically an electrically conducting polymer and facilitates the        injection of holes from the anode into the EL material layer.        The buffer layer may also have other properties which facilitate        device performance.

There is a continuing need for buffer materials with improvedproperties.

SUMMARY

There is provided an electrically conductive polymer compositioncomprising an electrically conductive polymer and apartially-fluorinated acid polymer, wherein at least 50% of the acidprotons are replaced with a cation selected from inorganic cations,organic cations, and combinations thereof.

In one embodiment, the polymeric acid is a water-solublepartially-fluorinated sulfonic acid polymer.

In another embodiment, there is provided an aqueous dispersion of anelectrically conductive polymer and a partially-fluorinated acidpolymer.

In another embodiment, electronic devices comprising at least one layercomprising the new conductive polymer composition are provided.

The foregoing general description and the following detailed descriptionare exemplary and explanatory only and are not restrictive of theinvention, as defined in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments are illustrated in the accompanying figures to improveunderstanding of concepts as presented herein.

FIG. 1 includes a diagram illustrating a contact angle.

FIG. 2 includes an illustration of an electronic device having a highenergy-potential bilayer composition.

Skilled artisans will appreciate that objects in the figures areillustrated for simplicity and clarity and have not necessarily beendrawn to scale. For example, the dimensions of some of the objects inthe figures may be magnified relative to other objects to help toimprove understanding of embodiments.

DETAILED DESCRIPTION

Many aspects and embodiments are described herein and are exemplary andnon-limiting. After reading this specification, skilled artisans willappreciate that other aspects and embodiments are possible withoutdeparting from the scope of the disclosure and appended claims.

Other features and benefits of any one or more of the embodiments willbe apparent from the following detailed description and from the claims.The detailed description first addresses Definitions and Clarificationof Terms followed by the Conductive Polymer, the Partially-FluorinatedAcid Polymer, Cations, Methods of Making the Conductive Compositions,Electronic Devices, and finally, Examples.

Definitions and Clarification of Terms Used in the Specification andClaims

Before addressing details of embodiments described below, some terms aredefined or clarified.

As used herein the term “conductor” and its variants are intended torefer to a layer material, member, or structure having an electricalproperty such that current flows through such layer material, member, orstructure without a substantial drop in potential. The term is intendedto include semiconductors. In one embodiment, a conductor will form alayer having a conductivity of at least 10⁻⁷ S/cm.

The term “electrically conductive material” refers to a material whichis inherently or intrinsically capable of electrical conductivitywithout the addition of carbon black or conductive metal particles.

The term “hole injection” when referring to a layer, material, member,or structure, is intended to mean such layer, material, member, orstructure facilitates injection and migration of positive chargesthrough the thickness of such layer, material, member, or structure withrelative efficiency and small loss of charge.

“Hole transport” when referring to a layer, material, member, orstructure, is intended to mean such layer, material, member, orstructure facilitates migration of positive charges through thethickness of such layer, material, member, or structure with relativeefficiency and small loss of charge. As used herein, the term “holetransport layer” does not encompass a light-emitting layer, even thoughthat layer may have some hole transport properties.

The term “polymer” is intended to mean a material having at least onerepeating monomeric unit. The term includes homopolymers having only onekind, or species, of monomeric unit, and copolymers having two or moredifferent monomeric units, including copolymers formed from monomericunits of different species.

The term “partially-fluorinated acid polymer” refers to a polymer havingacidic groups, where at least some, but not all of the hydrogens havebeen replaced by fluorine. In one embodiment, the partially-fluorinatedacid polymer has 20-80% of the hydrogens replaced by fluorine; in oneembodiment, 40-60% are replaced.

The term “acidic group” refers to a group capable of ionizing to donatea hydrogen ion to a base.

The composition may comprise one or more different electricallyconductive polymers and one or more different partially-fluorinated acidpolymers.

The term “doped” is intended to mean that the electrically conductivepolymer has a polymeric counterion to balance the charge on theconductive polymer.

The term “in admixture with” is intended to mean that an electricallyconductive polymer is physically mixed with a fluorinated acid polymer.

As used herein, the terms “comprises,” “comprising,” “includes,”“including,” “has,” “having” or any other variation thereof, areintended to cover a non-exclusive inclusion. For example, a process,method, article, or apparatus that comprises a list of elements is notnecessarily limited to only those elements but may include otherelements not expressly listed or inherent to such process, method,article, or apparatus. Further, unless expressly stated to the contrary,“or” refers to an inclusive or and not to an exclusive or. For example,a condition A or B is satisfied by any one of the following: A is true(or present) and B is false (or not present), A is false (or notpresent) and B is true (or present), and both A and B are true (orpresent).

Also, use of “a” or “an” are employed to describe elements andcomponents described herein. This is done merely for convenience and togive a general sense of the scope of the invention. This descriptionshould be read to include one or at least one and the singular alsoincludes the plural unless it is obvious that it is meant otherwise.

Group numbers corresponding to columns within the Periodic Table of theelements use the “New Notation” convention as seen in the CRC Handbookof Chemistry and Physics, 81^(st) Edition (2000-2001).

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. Although methods and materialssimilar or equivalent to those described herein can be used in thepractice or testing of embodiments of the present invention, suitablemethods and materials are described below. All publications, patentapplications, patents, and other references mentioned herein areincorporated by reference in their entirety, unless a particular passageis cited In case of conflict, the present specification, includingdefinitions, will control. In addition, the materials, methods, andexamples are illustrative and not intended to be limiting.

To the extent not described herein, many details regarding specificmaterials, processing acts, and circuits are conventional and may befound in textbooks and other sources within the organic light-emittingdiode display, lighting source, photodetector, photovoltaic, andsemiconductive member arts.

1. Conductive Polymer

In one embodiment, the conductive polymer will form a film which has aconductivity of at least 10⁻⁷ S/cm. The monomer from which theconductive polymer is formed, is referred to as a “precursor monomer”. Acopolymer will have more than one precursor monomer.

In one embodiment, the conductive polymer is made from at least oneprecursor monomer selected from thiophenes, selenophenes, tellurophenes,pyrroles, anilines, and polycyclic aromatics. The polymers made fromthese monomers are referred to herein as polythiophenes,poly(selenophenes), poly(tellurophenes), polypyrroles, polyanilines, andpolycyclic aromatic polymers, respectively. The term “polycyclicaromatic” refers to compounds having more than one aromatic ring. Therings may be joined by one or more bonds, or they may be fused together.The term “aromatic ring” is intended to include heteroaromatic rings. A“polycyclic heteroaromatic” compound has at least one heteroaromaticring. In one embodiment, the polycyclic aromatic polymers arepoly(thienothiophenes).

In one embodiment, monomers contemplated for use to form theelectrically conductive polymer in the new composition comprise FormulaI below:

wherein:

-   -   Q is selected from the group consisting of S, Se, and Te;    -   R¹ is independently selected so as to be the same or different        at each occurrence and is selected from hydrogen, alkyl,        alkenyl, alkoxy, alkanoyl, alkylthio, aryloxy, alkylthioalkyl,        alkylaryl, arylalkyl, amino, alkylamino, dialkylamino, aryl,        alkylsulfinyl, alkoxyalkyl, alkylsulfonyl, arylthio,        arylsulfinyl, alkoxycarbonyl, arylsulfonyl, acrylic acid,        phosphoric acid, phosphonic acid, halogen, nitro, cyano,        hydroxyl, epoxy, silane, siloxane, alcohol, benzyl, carboxylate,        ether, ether carboxylate, amidosulfonate, ether sulfonate, ester        sulfonate, and urethane; or both R¹ groups together may form an        alkylene or alkenylene chain completing a 3, 4, 5, 6, or        7-membered aromatic or alicyclic ring, which ring may optionally        include one or more divalent nitrogen, selenium, tellurium,        sulfur or oxygen atoms.

As used herein, the term “alkyl” refers to a group derived from analiphatic hydrocarbon and includes linear, branched and cyclic groupswhich may be unsubstituted or substituted. The term “heteroalkyl” isintended to mean an alkyl group, wherein one or more of the carbon atomswithin the alkyl group have been replaced by another atom, such asnitrogen, oxygen, sulfur, and the like. The term “alkylene” refers to analkyl group having two points of attachment.

As used herein, the term “alkenyl” refers to a group derived from analiphatic hydrocarbon having at least one carbon-carbon double bond, andincludes linear, branched and cyclic groups which may be unsubstitutedor substituted. The term “heteroalkenyl” is intended to mean an alkenylgroup, wherein one or more of the carbon atoms within the alkenyl grouphave been replaced by another atom, such as nitrogen, oxygen, sulfur,and the like. The term “alkenylene” refers to an alkenyl group havingtwo points of attachment.

As used herein, the following terms for substituent groups refer to theformulae given below:“alcohol” —R³—OH“amido” —R³—C(O)N(R⁶)R⁶“amidosulfonate” —R³—C(O)N(R⁶)R⁴— SO₃Z“benzyl” —CH₂—C₆H₅“carboxylate” —R³—C(O)O—Z or —R³—O—C(O)—Z“ether” —R³—(O—R⁵)_(p)—O—R⁵“ether carboxylate” —R³—O—R⁴—C(O)O—Z or —R³—O—R⁴—O—C(O)—Z“ether sulfonate” —R³—O—R⁴—SO₃Z“ester sulfonate” —R³—O—C(O)—R⁴—SO₃Z“sulfonimide” —R³—SO₂—NH—SO₂—R⁵“urethane” —R³—O—C(O)—N(R⁶)₂

-   -   where all “R” groups are the same or different at each        occurrence and:        -   R³ is a single bond or an alkylene group        -   R⁴ is an alkylene group        -   R⁵ is an alkyl group        -   R⁶ is hydrogen or an alkyl group        -   p is 0 or an integer from 1 to 20        -   Z is H, alkali metal, alkaline earth metal, N(R⁵)₄ or R⁵            Any of the above groups may, further, be unsubstituted or            substituted, and any group may have F substituted for one or            more hydrogens, and may comprise perfluorinated groups. In            one embodiment, the alkyl and alkylene groups have from 1-20            carbon atoms.

In one embodiment, in the monomer, both R¹ together form—O—(CHY)_(m)—O—, where m is 2 or 3, and Y is the same or different ateach occurrence and is selected from hydrogen, halogen, alkyl, alcohol,amidosulfonate, benzyl, carboxylate, ether, ether carboxylate, ethersulfonate, ester sulfonate, and urethane, where the Y groups may bepartially or fully fluorinated. In one embodiment, all Y are hydrogen.In one embodiment, the polymer is poly(3,4-ethylenedioxythiophene). Inone embodiment, at least one Y group is not hydrogen. In one embodiment,at least one Y group is a substituent having F substituted for at leastone hydrogen. In one embodiment, at least one Y group is perfluorinated.

In one embodiment, the monomer has Formula I(a):

wherein:

-   -   Q is selected from the group consisting of S, Se, and Te;    -   R⁷ is the same or different at each occurrence and is selected        from hydrogen, alkyl, heteroalkyl, alkenyl, heteroalkenyl,        alcohol, amidosulfonate, benzyl, carboxylate, ether, ether        carboxylate, ether sulfonate, ester sulfonate, and urethane,        with the proviso that at least one R⁷ is not hydrogen, and    -   m is 2 or 3.

In one embodiment of Formula I(a), m is two, one R⁷ is an alkyl group ofmore than 5 carbon atoms, and all other R⁷ are hydrogen. In oneembodiment of Formula I(a), at least one R⁷ group is fluorinated. In oneembodiment, at least one R⁷ group has at least one fluorine substituent.In one embodiment, the R⁷ group is fully fluorinated.

In one embodiment of Formula I(a), the R⁷ substituents on the fusedalicyclic ring on the monomer offer improved solubility of the monomersin water and facilitate polymerization in the presence of thefluorinated acid polymer.

In one embodiment of Formula I(a), m is 2, one R⁷ is sulfonicacid-propylene-ether-methylene and all other R⁷ are hydrogen. In oneembodiment, m is 2, one R⁷ is propyl-ether-ethylene and all other R⁷ arehydrogen. In one embodiment, m is 2, one R⁷ is methoxy and all other R⁷are hydrogen. In one embodiment, one R⁷ is sulfonic aciddifluoromethylene ester methylene (—CH₂—O—C(O)—CF₂—SO₃H), and all otherR⁷ are hydrogen.

In one embodiment, pyrrole monomers contemplated for use to form theelectrically conductive polymer in the new composition comprise FormulaII below.

where in Formula II:

-   -   R¹ is independently selected so as to be the same or different        at each occurrence and is selected from hydrogen, alkyl,        alkenyl, alkoxy, alkanoyl, alkylthio, aryloxy, alkylthioalkyl,        alkylaryl, arylalkyl, amino, alkylamino, dialkylamino, aryl,        alkylsulfinyl, alkoxyalkyl, alkylsulfonyl, arylthio,        arylsulfinyl, alkoxycarbonyl, arylsulfonyl, acrylic acid,        phosphoric acid, phosphonic acid, halogen, nitro, cyano,        hydroxyl, epoxy, silane, siloxane, alcohol, benzyl, carboxylate,        ether, amidosulfonate, ether carboxylate, ether sulfonate, ester        sulfonate, and urethane; or both R¹ groups together may form an        alkylene or alkenylene chain completing a 3, 4, 5, 6, or        7-membered aromatic or alicyclic ring, which ring may optionally        include one or more divalent nitrogen, sulfur, selenium,        tellurium, or oxygen atoms; and    -   R² is independently selected so as to be the same or different        at each occurrence and is selected from hydrogen, alkyl,        alkenyl, aryl, alkanoyl, alkylthioalkyl, alkylaryl, arylalkyl,        amino, epoxy, silane, siloxane, alcohol, benzyl, carboxylate,        ether, ether carboxylate, ether sulfonate, ester sulfonate, and        urethane.

In one embodiment, R¹ is the same or different at each occurrence and isindependently selected from hydrogen, alkyl, alkenyl, alkoxy,cycloalkyl, cycloalkenyl, alcohol, benzyl, carboxylate, ether,amidosulfonate, ether carboxylate, ether sulfonate, ester sulfonate,urethane, epoxy, silane, siloxane, and alkyl substituted with one ormore of sulfonic acid, carboxylic acid, acrylic acid, phosphoric acid,phosphonic acid, halogen, nitro, cyano, hydroxyl, epoxy, silane, orsiloxane moieties.

In one embodiment, R² is selected from hydrogen, alkyl, and alkylsubstituted with one or more of sulfonic acid, carboxylic acid, acrylicacid, phosphoric acid, phosphonic acid, halogen, cyano, hydroxyl, epoxy,silane, or siloxane moieties.

In one embodiment, the pyrrole monomer is unsubstituted and both R¹ andR² are hydrogen.

In one embodiment, both R¹ together form a 6- or 7-membered alicyclicring, which is further substituted with a group selected from alkyl,heteroalkyl, alcohol, benzyl, carboxylate, ether, ether carboxylate,ether sulfonate, ester sulfonate, and urethane. These groups can improvethe solubility of the monomer and the resulting polymer. In oneembodiment, both R¹ together form a 6- or 7-membered alicyclic ring,which is further substituted with an alkyl group. In one embodiment,both R¹ together form a 6- or 7-membered alicyclic ring, which isfurther substituted with an alkyl group having at least 1 carbon atom.

In one embodiment, both R¹ together form —O—(CHY)_(m)—O—, where m is 2or 3, and Y is the same or different at each occurrence and is selectedfrom hydrogen, alkyl, alcohol, benzyl, carboxylate, amidosulfonate,ether, ether carboxylate, ether sulfonate, ester sulfonate, andurethane. In one embodiment, at least one Y group is not hydrogen. Inone embodiment, at least one Y group is a substituent having Fsubstituted for at least one hydrogen. In one embodiment, at least one Ygroup is perfluorinated.

In one embodiment, aniline monomers contemplated for use to form theelectrically conductive polymer in the new composition comprise FormulaIII below.

wherein:

a is 0 or an integer from 1 to 4;

b is an integer from 1 to 5, with the proviso that a+b=5; and R¹ isindependently selected so as to be the same or different at eachoccurrence and is selected from hydrogen, alkyl, alkenyl, alkoxy,alkanoyl, alkylthio, aryloxy, alkylthioalkyl, alkylaryl, arylalkyl,amino, alkylamino, dialkylamino, aryl, alkylsulfinyl, alkoxyalkyl,alkylsulfonyl, arylthio, arylsulfinyl, alkoxycarbonyl, arylsulfonyl,acrylic acid, phosphoric acid, phosphonic acid, halogen, nitro, cyano,hydroxyl, epoxy, silane, siloxane, alcohol, benzyl, carboxylate, ether,ether carboxylate, amidosulfonate, ether sulfonate, ester sulfonate, andurethane; or both R¹ groups together may form an alkylene or alkenylenechain completing a 3, 4, 5, 6, or 7-membered aromatic or alicyclic ring,which ring may optionally include one or more divalent nitrogen, sulfuror oxygen atoms.

When polymerized, the aniline monomeric unit can have Formula IV(a) orFormula IV(b) shown below, or a combination of both formulae.

where a, b and R¹ are as defined above.

In one embodiment, the aniline monomer is unsubstituted and a=0.

In one embodiment, a is not 0 and at least one R¹ is fluorinated. In oneembodiment, at least one R¹ is perfluorinated.

In one embodiment, fused polycyclic heteroaromatic monomers contemplatedfor use to form the electrically conductive polymer in the newcomposition have two or more fused aromatic rings, at least one of whichis heteroaromatic. In one embodiment, the fused polycyclicheteroaromatic monomer has Formula V:

wherein:

-   -   Q is S, Se, Te, or NR⁶;    -   R⁶ is hydrogen or alkyl;    -   R⁸, R⁹, R¹⁰, and R¹¹ are independently selected so as to be the        same or different at each occurrence and are selected from        hydrogen, alkyl, alkenyl, alkoxy, alkanoyl, alkylthio, aryloxy,        alkylthioalkyl, alkylaryl, arylalkyl, amino, alkylamino,        dialkylamino, aryl, alkylsulfinyl, alkoxyalkyl, alkylsulfonyl,        arylthio, arylsulfinyl, alkoxycarbonyl, arylsulfonyl, acrylic        acid, phosphoric acid, phosphonic acid, halogen, nitro, nitrile,        cyano, hydroxyl, epoxy, silane, siloxane, alcohol, benzyl,        carboxylate, ether, ether carboxylate, amidosulfonate, ether        sulfonate, ester sulfonate, and urethane; and    -   at least one of R⁸ and R⁹, R⁹ and R¹⁰, and R¹⁰ and R¹¹ together        form an alkenylene chain completing a 5 or 6-membered aromatic        ring, which ring may optionally include one or more divalent        nitrogen, sulfur, selenium, tellurium, or oxygen atoms.

In one embodiment, the fused polycyclic heteroaromatic monomer hasFormula V(a), V(b), V(c), V(d), V(e), V(f), and V(g):

wherein:

-   -   Q is S, Se, Te, or NH; and    -   T is the same or different at each occurrence and is selected        from S, NR⁶, O, SiR⁶ ₂, Se, Te, and PR⁶;    -   R⁶ is hydrogen or alkyl.        The fused polycyclic heteroaromatic monomers may be substituted        with groups selected from alkyl, heteroalkyl, alcohol, benzyl,        carboxylate, ether, ether carboxylate, ether sulfonate, ester        sulfonate, and urethane. In one embodiment, the substituent        groups are fluorinated. In one embodiment, the substituent        groups are fully fluorinated.

In one embodiment, the fused polycyclic heteroaromatic monomer is athieno(thiophene). Such compounds have been discussed in, for example,Macromolecules, 34, 5746-5747 (2001); and Macromolecules, 35, 7281-7286(2002). In one embodiment, the thieno(thiophene) is selected fromthieno(2,3-b)thiophene, thieno(3,2-b)thiophene, andthieno(3,4-b)thiophene. In one embodiment, the thieno(thiophene) monomeris substituted with at least one group selected from alkyl, heteroalkyl,alcohol, benzyl, carboxylate, ether, ether carboxylate, ether sulfonate,ester sulfonate, and urethane. In one embodiment, the substituent groupsare fluorinated. In one embodiment, the substituent groups are fullyfluorinated.

In one embodiment, polycyclic heteroaromatic monomers contemplated foruse to form the polymer in the new composition comprise Formula VI:

wherein:

-   -   Q is S, Se, Te, or NR⁶;    -   T is selected from S, NR⁶, O, SiR⁶ ₂, Se, Te, and PR⁶;    -   E is selected from alkenylene, arylene, and heteroarylene;    -   R⁶ is hydrogen or alkyl;        -   R¹² is the same or different at each occurrence and is            selected from hydrogen, alkyl, alkenyl, alkoxy, alkanoyl,            alkylthio, aryloxy, alkylthioalkyl, alkylaryl, arylalkyl,            amino, alkylamino, dialkylamino, aryl, alkylsulfinyl,            alkoxyalkyl, alkylsulfonyl, arylthio, arylsulfinyl,            alkoxycarbonyl, arylsulfonyl, acrylic acid, phosphoric acid,            phosphonic acid, halogen, nitro, nitrile, cyano, hydroxyl,            epoxy, silane, siloxane, alcohol, benzyl, carboxylate,            ether, ether carboxylate, amidosulfonate, ether sulfonate,            ester sulfonate, and urethane; or both R¹² groups together            may form an alkylene or alkenylene chain completing a 3, 4,            5, 6, or 7-membered aromatic or alicyclic ring, which ring            may optionally include one or more divalent nitrogen,            sulfur, selenium, tellurium, or oxygen atoms.

In one embodiment, the electrically conductive polymer is a copolymer ofa precursor monomer and at least one second monomer. Any type of secondmonomer can be used, so long as it does not detrimentally affect thedesired properties of the copolymer. In one embodiment, the secondmonomer comprises no more than 50% of the copolymer, based on the totalnumber of monomer units. In one embodiment, the second monomer comprisesno more than 30%, based on the total number of monomer units. In oneembodiment, the second monomer comprises no more than 10%, based on thetotal number of monomer units.

Exemplary types of second monomers include, but are not limited to,alkenyl, alkynyl, arylene, and heteroarylene. Examples of secondmonomers include, but are not limited to, fluorene, oxadiazole,thiadiazole, benzothiadiazole, phenylenevinylene, phenyleneethynylene,pyridine, diazines, and triazines, all of which may be substituted.

In one embodiment, the copolymers are made by first forming anintermediate precursor monomer having the structure A-B-C, where A and Crepresent first precursor monomers, which can be the same or different,and B represents a second precursor monomer. The A-B-C intermediateprecursor monomer can be prepared using standard synthetic organictechniques, such as Yamamoto, Stille, Grignard metathesis, Suzuki, andNegishi couplings. The copolymer is then formed by oxidativepolymerization of the intermediate precursor monomer alone, or with oneor more additional precursor monomers.

In one embodiment, the electrically conductive polymer is a copolymer oftwo or more precursor monomers. In one embodiment, the precursormonomers are selected from a thiophene, a selenophene, a tellurophene, apyrrole, an aniline, and a polycyclic aromatic.

2. Partially-Fluorinated Acid Polymers

The partially-fluorinated acid polymer (“PFAP”) can be any polymer whichis partially fluorinated and has acidic groups with acidic protons. Theacidic groups supply an ionizable proton. In one embodiment, the acidicproton has a pKa of less than 3. In one embodiment, the acidic protonhas a pKa of less than 0. In one embodiment, the acidic proton has a pKaof less than −5. The acidic group can be attached directly to thepolymer backbone, or it can be attached to side chains on the polymerbackbone. Examples of acidic groups include, but are not limited to,carboxylic acid groups, sulfonic acid groups, sulfonimide groups,phosphoric acid groups, phosphonic acid groups, and combinationsthereof. The acidic groups can all be the same, or the polymer may havemore than one type of acidic group. In one embodiment, the acidic groupsare selected from the group consisting of sulfonic acid groups,sulfonamide groups, and combinations thereof.

In one embodiment, the PFAP is water-soluble. In one embodiment, thePFAP is dispersible in water.

In one embodiment, the PFAP is organic solvent wettable. The term“organic solvent wettable” refers to a material which, when formed intoa film, is wettable by organic solvents. In one embodiment, wettablematerials form films which are wettable by phenylhexane with a contactangle no greater than 40°. As used herein, the term “contact angle” isintended to mean the angle φ shown in FIG. 1. For a droplet of liquidmedium, angle φ is defined by the intersection of the plane of thesurface and a line from the outer edge of the droplet to the surface.Furthermore, angle φ is measured after the droplet has reached anequilibrium position on the surface after being applied, i.e., “staticcontact angle”. The film of the organic solvent wettable fluorinatedpolymeric acid is represented as the surface. In one embodiment, thecontact angle is no greater than 35°. In one embodiment, the contactangle is no greater than 30°. The methods for measuring contact anglesare well known.

In one embodiment, the polymer backbone is fluorinated. Examples ofsuitable polymeric backbones include, but are not limited to,polyolefins, polyacrylates, polymethacrylates, polyimides, polyamides,polyaramids, polyacrylamides, polystyrenes, and copolymers thereof. Inone embodiment, the polymer backbone is highly fluorinated. In oneembodiment, the polymer backbone is fully fluorinated.

In one embodiment, the acidic groups are sulfonic acid groups orsulfonimide groups. A sulfonimide group has the formula:—SO₂—NH—SO₂—Rwhere R is an alkyl group.

In one embodiment, the acidic groups are on a fluorinated side chain. Inone embodiment, the fluorinated side chains are selected from alkylgroups, alkoxy groups, amido groups, ether groups, and combinationsthereof.

In one embodiment, the PFAP has a fluorinated olefin backbone, withpendant fluorinated ether sulfonate, fluorinated ester sulfonate, orfluorinated ether sulfonimide groups. In one embodiment, the polymer isa copolymer of 1,1-difluoroethylene and2-(1,1-difluoro-2-(trifluoromethyl)allyloxy)-1,1,2,2-tetrafluoroethanesulfonicacid. In one embodiment, the polymer is a copolymer of ethylene and2-(2-(1,2,2-trifluorovinyloxy)-1,1,2,3,3,3-hexafluoropropoxy)-1,1,2,2-tetrafluoroethanesulfonicacid. These copolymers can be made as the corresponding sulfonylfluoride polymer and then can be converted to the sulfonic acid form.

In one embodiment, the PFAP is a homopolymer or copolymer of afluorinated and partially sulfonated poly(arylene ether sulfone). Thecopolymer can be a block copolymer. Examples of comonomers include, butare not limited to butadiene, butylene, isobutylene, styrene, andcombinations thereof.

In one embodiment, the PFAP is a homopolymer or copolymer of monomershaving Formula VII:

where:

-   -   b is an integer from 1 to 5,    -   R¹³ is OH or NHR¹⁴, and    -   R¹⁴ is alkyl, fluoroalkyl, sulfonylalkyl, or        sulfonylfluoroalkyl.        In one embodiment, the monomer is “SFS” or SFSI” shown below:

After polymerization, the polymer can be converted to the acid form.

In one embodiment, the PFAP is a homopolymer or copolymer of atrifluorostyrene having acidic groups. In one embodiment, thetrifluorostyrene monomer has Formula VIII:

where:

-   -   W is selected from (CF₂)_(q), O(CF₂)_(q), S(CF₂)_(q),        (CF₂)_(q)O(CF₂)_(r), and SO₂(CF₂)_(q),    -   b is independently an integer from 1 to 5,    -   R¹³ is OH or NHR¹⁴, and    -   R¹⁴ is alkyl, fluoroalkyl, sulfonylalkyl, or        sulfonylfluoroalkyl.        In one embodiment, the monomer containing W equal to S(CF₂)_(q)        is polymerized then oxidized to give the polymer containing W        equal to SO₂(CF₂)_(q). In one embodiment, the polymer containing        R¹³ equal to F is converted its acid form where R¹³ is equal to        OH or NHR¹⁴.

In one embodiment, the PFAP is a sulfonimide polymer having Formula IX:

where:

-   -   R_(f) is selected from fluorinated alkylene, fluorinated        heteroalkylene, fluorinated arylene, or fluorinated        heteroarylene;    -   R_(g) is selected from fluorinated alkylene, fluorinated        heteroalkylene, fluorinated arylene, fluorinated heteroarylene,        arylene, or heteroarylene; and    -   n is at least 4.        In one embodiment of Formula IX, R_(f) and R_(g) are        perfluoroalkylene groups. In one embodiment, R_(f) and R_(g) are        perfluorobutylene groups. In one embodiment, R_(f) and R_(g)        contain ether oxygens. In one embodiment, n is greater than 20.

In one embodiment, the PFAP comprises a fluorinated polymer backbone anda side chain having Formula X:

where:

-   -   R_(g) is selected from fluorinated alkylene, fluorinated        heteroalkylene, fluorinated arylene, fluorinated heteroarylene,        arylene, or heteroarylene;    -   R¹⁵ is a fluorinated alkylene group or a fluorinated        heteroalkylene group;    -   R¹⁶ is a fluorinated alkyl or a fluorinated aryl group; and    -   a is 0 or an integer from 1 to 4.

In one embodiment, the PFAP has Formula XI:

where:

-   -   R¹⁶ is a fluorinated alkyl or a fluorinated aryl group;    -   a, b, c, d, and e are each independently 0 or an integer from 1        to 4; and    -   n is at least 4.

The synthesis of PFAPs has been described in, for example, A. Feiring etal., J. Fluorine Chemistry 2000, 105, 129-135; A. Feiring et al.,Macromolecules 2000, 33, 9262-9271; D. D. Desmarteau, J. Fluorine Chem.1995, 72, 203-208; A. J. Appleby et al., J. Electrochem. Soc. 1993,140(1), 109-111; and Desmarteau, U.S. Pat. No. 5,463,005.

In one embodiment, the PFAP comprises at least one repeat unit derivedfrom an ethylenically unsaturated compound having Formula XII:

-   -   wherein d is 0, 1, or 2;    -   R¹⁷ to R²⁰ are independently H, halogen, alkyl or alkoxy of 1 to        10 carbon atoms, Y, C(R_(f)′)(R_(f)′)OR²¹, R⁴Y or OR⁴Y;    -   Y is COE², SO₂E², or sulfonimide;    -   R²¹ is hydrogen or an acid-labile protecting group;    -   R_(f)′ is the same or different at each occurrence and is a        fluoroalkyl group of 1 to 10 carbon atoms, or taken together are        (CF₂)_(e) where e is 2 to 10;    -   R⁴ is an alkylene group;    -   E² is OH, halogen, or OR⁵; and    -   R⁵ is an alkyl group;

with the proviso that at least one of R¹⁷ to R²⁰ is Y, R⁴Y or OR⁵Y. R⁴,R⁵, and R¹⁷ to R²⁰ may optionally be substituted by halogen or etheroxygen.

Some illustrative, but nonlimiting, examples of representative monomersof Formula XII and within the scope of the invention are presented inFormulas XIIa through XIIe (right to left) below:

wherein R²¹ is a group capable of forming or rearranging to a tertiarycation, more typically an alkyl group of 1 to 20 carbon atoms, and mosttypically t-butyl.

Compounds of Formula XII wherein d=0, such as Formula XII-a, may beprepared by cycloaddition reaction of unsaturated compounds of FormulaXIII with quadricyclane (tetracyclo[2.2.1.0^(2,6)0^(3,5)]heptane) asshown in the equation below.

The reaction may be conducted at temperatures ranging from about 0° C.to about 200° C., more typically from about 30° C. to about 150° C. inthe absence or presence of an inert solvent such as diethyl ether. Forreactions conducted at or above the boiling point of one or more of thereagents or solvent, a closed reactor is typically used to avoid loss ofvolatile components. Compounds of Formula XII with higher values of d(i.e., d=1 or 2) may be prepared by reaction of compounds of structure(XII) with d=0 with cyclopentadiene, as is known in the art.

In one embodiment, the PFAP also comprises a repeat unit derived from atleast one ethylenically unsaturated compound containing at least onefluorine atom attached to an ethylenically unsaturated carbon. Thefluoroolefin comprises 2 to 20 carbon atoms. Representativefluoroolefins include, but are not limited to, tetrafluoroethylene,hexafluoropropylene, chlorotrifluoroethylene, vinylidene fluoride, vinylfluoride, perfluoro-(2,2-dimethyl-1,3-dioxole),perfluoro-(2-methylene-4-methyl-1,3-dioxolane), CF₂═CFO(CF₂)_(t)CF═CF₂,where t is 1 or 2, and R_(f)″OCF═CF₂ wherein R_(f)″ is a saturatedfluoroalkyl group of from 1 to about ten carbon atoms. In oneembodiment, the comonomer is tetrafluoroethylene.

In one embodiment, the PFAP comprises a polymeric backbone havingpendant groups comprising siloxane sulfonic acid. In one embodiment, thesiloxane pendant groups have the formula below:—O_(a)Si(OH)_(b-a)R²² _(3-b)R²³R_(f)SO₃H

wherein:

a is from 1 to b;

b is from 1 to 3;

R²² is a non-hydrolyzable group independently selected from the groupconsisting of alkyl, aryl, and arylalkyl;

R²³ is a bidentate alkylene radical, which may be substituted by one ormore ether oxygen atoms, with the proviso that R²³ has at least twocarbon atoms linearly disposed between Si and R_(f); and

R_(f) is a perfluoralkylene radical, which may be substituted by one ormore ether oxygen atoms.

In one embodiment, the PFAP having pendant siloxane groups has afluorinated backbone. In one embodiment, the backbone is perfluorinated.

In one embodiment, the PFAP has a non-fluorinated orpartially-fluorinated backbone and pendant groups represented by theFormula (XIV)—O_(g)—[CF(R_(f) ²)CF—O_(h)]_(i)—CF₂CF₂SO₃H  (XIV)

-   -   wherein R_(f) ² is F or a perfluoroalkyl radical having 1-10        carbon atoms either unsubstituted or substituted by one or more        ether oxygen atoms, h=0 or 1, i=0 to 3, and g=0 or 1.

In one embodiment, the PFAP has formula (XV)

where j≧0, k≧0 and 4≦(j+k)≦199, Q¹ and Q² are F or H, R_(f) ² is F or aperfluoroalkyl radical having 1-10 carbon atoms either unsubstituted orsubstituted by one or more ether oxygen atoms, h=0 or 1, i=0 to 3, g=0or 1. In one embodiment R_(f) ² is —CF₃, g=1, h=1, and i=1. In oneembodiment the pendant group is present at a concentration of 3-10mol-%.

In one embodiment, Q¹ is H, k≧0, and Q² is F, which may be synthesizedaccording to the teachings of Connolly et al., U.S. Pat. No. 3,282,875.In another preferred embodiment, Q¹ is H, Q² is H, g=0, R_(f) ² is F,h=1, and l=1, which may be synthesized according to the teachings ofco-pending application Ser. No. 60/105,662. Still other embodiments maybe synthesized according to the various teachings in Drysdale et al., WO9831716(A1), and co-pending US applications Choi et al, WO 99/52954(A1),and 60/176,881.

In one embodiment, the PFAP is a colloid-forming polymeric acid. As usedherein, the term “colloid-forming” refers to materials which areinsoluble in water, and form colloids when dispersed into an aqueousmedium. The colloid-forming polymeric acids typically have a molecularweight in the range of about 10,000 to about 4,000,000. In oneembodiment, the polymeric acids have a molecular weight of about 100,000to about 2,000,000. Colloid particle size typically ranges from 2nanometers (nm) to about 140 nm. In one embodiment, the colloids have aparticle size of 2 nm to about 30 nm. Any partially-fluorinatedcolloid-forming polymeric material having acidic protons can be used.

Some of the polymers described hereinabove may be formed in non-acidform, e.g., as salts, esters, or sulfonyl fluorides. They will beconverted to the acid form for the preparation of conductivecompositions, described below.

3. Cations

In one embodiment, the cations which replace the acidic protons areorganic cations. Examples of organic cations include, but are notlimited to, ammonium ions and ammonium ions substituted with one or morealkyl groups. In one embodiment, the alkyl groups have from 1-3 carbonatoms.

In one embodiment, some of the acidic protons are replaced with thepositively-charged conductive polymer. In one embodiment, the conductivepolymer is partially oxidized polyaniline in the emeraldine base form.In this form, the imine nitrogens are protonated.

In one embodiment, the cations which replace the acidic protons areinorganic cations. Examples of inorganic cations include, but are notlimited to, cations from Groups 1 and 2 of the Periodic Table. In oneembodiment, the inorganic cations are selected from the group consistingof Na+, K+, and combinations thereof.

The PFAP with acid protons replaced with cations, can be formed byreacting the PFAP with the cation base. For example, the acid form ofthe PFAP can be mixed with NaOH, to form the cation form of the PFAP.Alternatively, the PFAP can be treated with an ion exchange resin, asdiscussed below.

4. Preparation of Conductive Compositions

The new electrically conductive polymer composition is prepared by (i)polymerizing the precursor monomers in the presence of the PFAP; or (ii)first forming the intrinsically conductive copolymer and combining itwith the PFAP.

(i) Polymerizing Precursor Monomers in the Presence of the PFAP

In one embodiment, the electrically conductive polymer composition isformed by the oxidative polymerization of the precursor monomers in thepresence of the PFAP. In one embodiment, the precursor monomers comprisetwo or more conductive precursor monomers. In one embodiment, themonomers comprise an intermediate precursor monomer having the structureA-B-C, where A and C represent conductive precursor monomers, which canbe the same or different, and B represents a non-conductive precursormonomer. In one embodiment, the intermediate precursor monomer ispolymerized with one or more conductive precursor monomers.

In one embodiment, the oxidative polymerization is carried out in ahomogeneous aqueous solution. In another embodiment, the oxidativepolymerization is carried out in an emulsion of water and an organicsolvent. In general, some water is present in order to obtain adequatesolubility of the oxidizing agent and/or catalyst. Oxidizing agents suchas ammonium persulfate, sodium persulfate, potassium persulfate, and thelike, can be used. A catalyst, such as ferric chloride, or ferricsulfate may also be present. The resulting polymerized product will be asolution, dispersion, or emulsion of the conductive polymer inassociation with the PFAP. In one embodiment, the intrinsicallyconductive polymer is positively charged, and the charges are balancedby the PFAP anion.

In one embodiment, the method of making an aqueous dispersion of the newconductive polymer composition includes forming a reaction mixture bycombining water, precursor monomer, at least one PFAP, and an oxidizingagent, in any order, provided that at least a portion of the PFAP ispresent when at least one of the precursor monomer and the oxidizingagent is added.

In one embodiment, the method of making the new conductive polymercomposition comprises:

(a) providing an aqueous solution or dispersion of a PFAP;

(b) adding an oxidizer to the solutions or dispersion of step (a); and

(c) adding precursor monomer to the mixture of step (b).

In another embodiment, the precursor monomer is added to the aqueoussolution or dispersion of the PFAP prior to adding the oxidizer. Step(b) above, which is adding oxidizing agent, is then carried out.

In another embodiment, a mixture of water and the precursor monomer isformed, in a concentration typically in the range of about 0.5% byweight to about 4.0% by weight total precursor monomer. This precursormonomer mixture is added to the aqueous solution or dispersion of thePFAP, and steps (b) above which is adding oxidizing agent is carriedout.

In another embodiment, the aqueous polymerization mixture may include apolymerization catalyst, such as ferric sulfate, ferric chloride, andthe like. The catalyst is added before the last step. In anotherembodiment, a catalyst is added together with an oxidizing agent.

In one embodiment, the polymerization is carried out in the presence ofco-dispersing liquids which are miscible with water. Examples ofsuitable co-dispersing liquids include, but are not limited to ethers,alcohols, alcohol ethers, cyclic ethers, ketones, nitriles, sulfoxides,amides, and combinations thereof. In one embodiment, the co-dispersingliquid is an alcohol. In one embodiment, the co-dispersing liquid is anorganic solvent selected from n-propanol, isopropanol, t-butanol,dimethylacetamide, dimethylformamide, N-methylpyrrolidone, and mixturesthereof. In general, the amount of co-dispersing liquid should be lessthan about 60% by volume. In one embodiment, the amount of co-dispersingliquid is less than about 30% by volume. In one embodiment, the amountof co-dispersing liquid is between 5 and 50% by volume. The use of aco-dispersing liquid in the polymerization significantly reducesparticle size and improves filterability of the dispersions. Inaddition, buffer materials obtained by this process show an increasedviscosity and films prepared from these dispersions are of high quality.

The co-dispersing liquid can be added to the reaction mixture at anypoint in the process.

In one embodiment, the polymerization is carried out in the presence ofa co-acid which is a Brønsted acid. The acid can be an inorganic acid,such as HCl, sulfuric acid, and the like, or an organic acid, such asacetic acid or p-toluenesulfonic acid. Alternatively, the acid can be awater soluble polymeric acid such as poly(styrenesulfonic acid),poly(2-acrylamido-2-methyl-1-propanesulfonic acid, or the like, or asecond PFAP, as described above. Combinations of acids can be used.

The co-acid can be added to the reaction mixture at any point in theprocess prior to the addition of either the oxidizer or the precursormonomer, whichever is added last. In one embodiment, the co-acid isadded before both the precursor monomers and the PFAP, and the oxidizeris added last. In one embodiment the co-acid is added prior to theaddition of the precursor monomers, followed by the addition of thePFAP, and the oxidizer is added last.

In one embodiment, the polymerization is carried out in the presence ofboth a co-dispersing liquid and a co-acid.

In one embodiment, a reaction vessel is charged first with a mixture ofwater, alcohol co-dispersing agent, and inorganic co-acid. To this isadded, in order, the precursor monomers, an aqueous solution ordispersion of PFAP, and an oxidizer. The oxidizer is added slowly anddropwise to prevent the formation of localized areas of high ionconcentration which can destabilize the mixture. The mixture is stirredand the reaction is then allowed to proceed at a controlled temperature.When polymerization is completed, the reaction mixture is treated with astrong acid cation resin, stirred and filtered; and then treated with abase anion exchange resin, stirred and filtered. Alternative orders ofaddition can be used, as discussed above.

In the method of making the new conductive polymer composition, themolar ratio of oxidizer to total precursor monomer is generally in therange of 0.1 to 2.0; and in one embodiment is 0.4 to 1.5. The molarratio of PFAP to total precursor monomer is generally in the range of0.2 to 5. In one embodiment, the ratio is in the range of 1 to 4. Theoverall solid content is generally in the range of about 1.0% to 10% inweight percentage; and in one embodiment of about 2% to 4.5%. Thereaction temperature is generally in the range of about 4° C. to 50° C.;in one embodiment about 20° C. to 35° C. The molar ratio of optionalco-acid to precursor monomer is about 0.05 to 4. The addition time ofthe oxidizer influences particle size and viscosity. Thus, the particlesize can be reduced by slowing down the addition speed. In parallel, theviscosity is increased by slowing down the addition speed. The reactiontime is generally in the range of about 1 to about 30 hours.

(ii) Combining Intrinsically Conductive Polymers with PFAPs

In one embodiment, the intrinsically conductive polymers are formedseparately from the PFAP. In one embodiment, the polymers are preparedby oxidatively polymerizing the corresponding monomers in aqueoussolution. In one embodiment, the oxidative polymerization is carried outin the presence of a water-soluble non-fluorinated polymeric acid. Inone embodiment, the acid is a non-fluorinated polymeric sulfonic acid.Some non-limiting examples of the acids are poly(styrenesulfonic acid)(“PSSA”), poly(2-acrylamido-2-methyl-1-propanesulfonic acid)(“PAAMPSA”), and mixtures thereof. Where the oxidative polymerizationresults in a polymer that has positive charge, the acid anion providesthe counterion for the conductive polymer. The oxidative polymerizationis carried out using an oxidizing agent such as ammonium persulfate,sodium persulfate, and mixtures thereof.

The new electrically conductive polymer composition is prepared byblending the intrinsically conductive polymer with the PFAP. This can beaccomplished by adding an aqueous dispersion of the intrinsicallyconductive polymer to a dispersion or solution of the PFAP. In oneembodiment, the composition is further treated using sonication ormicrofluidization to ensure mixing of the components.

In one embodiment, one or both of the intrinsically conductive polymerand PFAP are isolated in solid form. The solid material can beredispersed in water or in an aqueous solution or dispersion of theother component. For example, intrinsically conductive polymer solidscan be dispersed in an aqueous solution or dispersion of a PFAP.

(iii) Replacement of Acidic Protons with Cations

In one embodiment, conductive polymer composition is contacted with atleast one ion exchange resin under conditions suitable to replace acidicprotons with cations. The composition may be treated with one or moretypes of ion exchange resins, simultaneously or sequentially.

Ion exchange is a reversible chemical reaction wherein an ion in a fluidmedium (such as an aqueous dispersion) is exchanged for a similarlycharged ion attached to an immobile solid particle that is insoluble inthe fluid medium. The term “ion exchange resin” is used herein to referto all such substances. The resin is rendered insoluble due to thecrosslinked nature of the polymeric support to which the ion exchanginggroups are attached. Ion exchange resins are classified as cationexchangers or anion exchangers. Cation exchangers have positivelycharged mobile ions available for exchange, typically metal ions such assodium ions. Anion exchangers have exchangeable ions which arenegatively charged, typically hydroxide ions.

In one embodiment, a first ion exchange resin is a cation, acid exchangeresin which can be in metal ion, typically sodium ion, form. A secondion exchange resin is a basic, anion exchange resin. Both acidic, cationproton exchange resins and basic, anion exchange resins can be used. Inone embodiment, the acidic, cation exchange resin is an inorganic acid,cation exchange resin, such as a sulfonic acid cation exchange resin.Sulfonic acid cation exchange resins contemplated for use in thepractice of the invention include, for example, sulfonatedstyrene-divinylbenzene copolymers, sulfonated crosslinked styrenepolymers, phenol-formaldehyde-sulfonic acid resins,benzene-formaldehyde-sulfonic acid resins, and mixtures thereof. Inanother embodiment, the acidic, cation exchange resin is an organicacid, cation exchange resin, such as carboxylic acid, acrylic orphosphorous cation exchange resin. In addition, mixtures of differentcation exchange resins can be used.

In another embodiment, the basic, anionic exchange resin is a tertiaryamine anion exchange resin. Tertiary amine anion exchange resinscontemplated for use in the practice of the invention include, forexample, tertiary-aminated styrene-divinylbenzene copolymers,tertiary-aminated crosslinked styrene polymers, tertiary-aminatedphenol-formaldehyde resins, tertiary-aminated benzene-formaldehyderesins, and mixtures thereof. In a further embodiment, the basic,anionic exchange resin is a quaternary amine anion exchange resin, ormixtures of these and other exchange resins.

In one embodiment, both types of resins are added simultaneously to aliquid composition comprising the electrically conducting polymer andPFAP, and allowed to remain in contact with the liquid composition forat least about 1 hour, e.g., about 2 hours to about 20 hours. The ionexchange resins can then be removed from the dispersion by filtration.The size of the filter is chosen so that the relatively large ionexchange resin particles will be removed while the smaller dispersionparticles will pass through. In general, about one to five grams of ionexchange resin is used per gram of new conductive polymer composition.

In some embodiments, the acidic protons are replaced by the addition ofan aqueous basic solution. Examples of such as a solution include, butare not limited to, sodium hydroxide, ammonium hydroxide,tetra-methylammonium hydroxide, and the like.

In one embodiment, greater than 50% of the acidic protons are replacedwith cations. In one embodiment, greater than 60% are replaced; in oneembodiment, greater than 75% are replaced; in one embodiment, greaterthan 90% are replaced.

(iv) Hole Transport Layer

Any hole transport material may be used for the hole transport layer. Inone embodiment the hole transport material has an optical band gap equalto or less than 4.2 eV and a HOMO level equal to or less than 6.2 eVwith respect to vacuum level.

In one embodiment, the hole transport material comprises at least onepolymer. Examples of hole transport polymers include those having holetransport groups. Such hole transport groups include, but are notlimited to, carbazole, triarylamines, triarylmethane, fluorene, andcombinations thereof.

In one embodiment, the hole transport layer comprises a non-polymerichole transport material. Examples of hole transporting moleculesinclude, but are not limited to:4,4′,4″-tris(N,N-diphenyl-amino)-triphenylamine (TDATA);4,4′,4″-tris(N-3-methylphenyl-N-phenyl-amino)-triphenylamine (MTDATA);N,N′-diphenyl-N,N′-bis(3-methylphenyl)-[1,1′-biphenyl]-4,4′-diamine(TPD); 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC);N,N′-bis(4-methylphenyl)-N,N′-bis(4-ethylphenyl)-[1,1′-(3,3′-dimethyl)biphenyl]-4,4′-diamine(ETPD); tetrakis-(3-methylphenyl)-N,N,N′,N′-2,5-phenylenediamine (PDA);α-phenyl-4-N,N-diphenylaminostyrene (TPS); p-(diethylamino)benzaldehydediphenylhydrazone (DEH); triphenylamine (TPA);bis[4-(N,N-diethylamino)-2-methylphenyl](4-methylphenyl)methane (MPMP);1-phenyl-3-[p-(diethylamino)styryl]-5-[p-(diethylamino)phenyl]pyrazoline(PPR or DEASP); 1,2-trans-bis(9H-carbazol-9-yl)cyclobutane (DCZB);N,N,N′,N′-tetrakis(4-methylphenyl)-(1,1′-biphenyl)-4,4′-diamine (TTB);N,N′-bis(naphthalen-1-yl)-N,N′-bis-(phenyl)benzidine (α-NPB); andporphyrinic compounds, such as copper phthalocyanine.

In one embodiment, the hole transport layer comprises a material havingthe Formula XVI:

wherein

-   -   Ar is an arylene group;    -   Ar′, and Ar″ are selected independently from aryl groups;    -   R²⁴ through R²⁷ are selected independently from the group        consisting of hydrogen, alkyl, aryl, halogen, hydroxyl, aryloxy,        alkoxy, alkenyl, alkynyl, amino, alkylthio, phosphino, silyl,        —COR, —COOR, —PO₃R₂, —OPO₃R₂, and CN;    -   R is selected from the group consisting of hydrogen, alkyl,        aryl, alkenyl, alkynyl, and amino; and    -   m and n are integers each independently having a value of from 0        to 5, where m+n≠0.        In one embodiment of Formula XVI, Ar is an arylene group        containing two or more ortho-fused benzene rings in a straight        linear arrangement.        (v) Methods of Making Bilayer Compositions

The hole injection and hole transport layers of the bilayer compositioncan be made using any technique for forming layers. In one embodiment,the hole injection layer is formed first, and the hole transport layeris formed directly on at least a part of the hole injection layer. Inone embodiment, the hole transport layer is formed directly on andcovering the entire hole injection layer.

In one embodiment, the hole injection layer is formed on a substrate byliquid deposition from a liquid composition. The term “substrate” isintended to mean a base material that can be either rigid or flexibleand may be include one or more layers of one or more materials.Substrate materials can include, but are not limited to, glass, polymer,metal or ceramic materials or combinations thereof. The substrate may ormay not include electronic components, circuits, conductive members, orlayers of other materials.

Any known liquid deposition technique can be used, including continuousand discontinuous techniques. Continuous liquid deposition techniques,include but are not limited to, spin coating, gravure coating, curtaincoating, dip coating, slot-die coating, spray coating, and continuousnozzle coating. Discontinuous liquid deposition techniques include, butare not limited to, ink jet printing, gravure printing, flexographicprinting and screen printing.

In one embodiment, the hole injection layer is formed by liquiddeposition from a liquid composition having a pH greater than 2. In oneembodiment, the pH is greater than 4. In one embodiment, the pH isgreater than 6.

In one embodiment, the hole transport layer is formed directly on atleast a part of the hole injection layer by liquid deposition from aliquid composition.

In one embodiment, the hole transport layer is formed by vapordeposition onto at least a part of the hole injection layer. Any vapordeposition technique can be used, including sputtering, thermalevaporation, chemical vapor deposition and the like. Chemical vapordeposition may be performed as a plasma-enhanced chemical vapordeposition (“PECVD”) or metal organic chemical vapor deposition(“MOCVD”). Physical vapor deposition can include all forms ofsputtering, including ion beam sputtering, as well as e-beam evaporationand resistance evaporation. Specific forms of physical vapor depositioninclude rf magnetron sputtering and inductively-coupled plasma physicalvapor deposition (“IMP-PVD”). These deposition techniques are well knownwithin the semiconductor fabrication arts.

The thickness of the hole injection layer can be as great as desired forthe intended use. In one embodiment, the hole injection layer has athickness in the range of 100 nm to 200 microns. In one embodiment, thehole injection layer has a thickness in the range of 50-500 nm. In oneembodiment, the hole injection layer has a thickness less than 50 nm. Inone embodiment, the hole injection layer has a thickness less than 10nm. In one embodiment, the hole injection layer has a thickness that isgreater than the thickness of the hole transport layer.

The thickness of the hole transport layer can be a little as a singlemonolayer. In one embodiment, the thickness is in the range of 100 nm to200 microns. In one embodiment, the thickness is less than 100 nm. Inone embodiment, the thickness is less than 10 nm. In one embodiment, thethickness is less than 1 nm.

5. Electronic Devices

In another embodiment of the invention, there are provided electronicdevices comprising at least one layer made from the conductive polymercomposition described herein. The term “electronic device” is intendedto mean a device including one or more organic semiconductor layers ormaterials. An electronic device includes, but is not limited to: (1) adevice that converts electrical energy into radiation (e.g., alight-emitting diode, light emitting diode display, diode laser, orlighting panel), (2) a device that detects a signal using an electronicprocess (e.g., a photodetector, a photoconductive cell, a photoresistor,a photoswitch, a phototransistor, a phototube, an infrared (“IR”)detector, or a biosensors), (3) a device that converts radiation intoelectrical energy (e.g., a photovoltaic device or solar cell), (4) adevice that includes one or more electronic components that include oneor more organic semiconductor layers (e.g., a transistor or diode), orany combination of devices in items (1) through (4).

In one embodiment, the electronic device comprises at least oneelectroactive layer positioned between two electrical contact layers,wherein the device further includes the bilayer. The term“electroactive” when referring to a layer or material is intended tomean a layer or material that exhibits electronic or electro-radiativeproperties. An electroactive layer material may emit radiation orexhibit a change in concentration of electron-hole pairs when receivingradiation.

As shown in FIG. 2, a typical device, 100, has an anode layer 110, abuffer layer 120, an electroactive layer 130, and a cathode layer 150.Adjacent to the cathode layer 150 is an optionalelectron-injection/transport layer 140.

The device may include a support or substrate (not shown) that can beadjacent to the anode layer 110 or the cathode layer 150. Mostfrequently, the support is adjacent the anode layer 110. The support canbe flexible or rigid, organic or inorganic. Examples of supportmaterials include, but are not limited to, glass, ceramic, metal, andplastic films.

The anode layer 110 is an electrode that is more efficient for injectingholes compared to the cathode layer 150. The anode can include materialscontaining a metal, mixed metal, alloy, metal oxide or mixed oxide.Suitable materials include the mixed oxides of the Group 2 elements(i.e., Be, Mg, Ca, Sr, Ba, Ra), the Group 11 elements, the elements inGroups 4, 5, and 6, and the Group 8-10 transition elements. If the anodelayer 110 is to be light transmitting, mixed oxides of Groups 12, 13 and14 elements, such as indium-tin-oxide, may be used. As used herein, thephrase “mixed oxide” refers to oxides having two or more differentcations selected from the Group 2 elements or the Groups 12, 13, or 14elements. Some non-limiting, specific examples of materials for anodelayer 110 include, but are not limited to, indium-tin-oxide (“ITO”),indium-zinc-oxide, aluminum-tin-oxide, gold, silver, copper, and nickel.The anode may also comprise an organic material, especially a conductingpolymer such as polyaniline, including exemplary materials as describedin “Flexible light-emitting diodes made from soluble conductingpolymer,” Nature vol. 357, pp 477 479 (11 Jun. 1992). At least one ofthe anode and cathode should be at least partially transparent to allowthe generated light to be observed.

The anode layer 110 may be formed by a chemical or physical vapordeposition process or spin-cast process. Chemical vapor deposition maybe performed as a plasma-enhanced chemical vapor deposition (“PECVD”) ormetal organic chemical vapor deposition (“MOCVD”). Physical vapordeposition can include all forms of sputtering, including ion beamsputtering, as well as e-beam evaporation and resistance evaporation.Specific forms of physical vapor deposition include rf magnetronsputtering and inductively-coupled plasma physical vapor deposition(“IMP-PVD”). These deposition techniques are well known within thesemiconductor fabrication arts.

In one embodiment, the anode layer 110 is patterned during alithographic operation. The pattern may vary as desired. The layers canbe formed in a pattern by, for example, positioning a patterned mask orresist on the first flexible composite barrier structure prior toapplying the first electrical contact layer material. Alternatively, thelayers can be applied as an overall layer (also called blanket deposit)and subsequently patterned using, for example, a patterned resist layerand wet chemical or dry etching techniques. Other processes forpatterning that are well known in the art can also be used.

The conductive polymer compositions described herein are suitable as thebuffer layer 120. The term “buffer layer” or “buffer material” isintended to mean electrically conductive or semiconductive materials andmay have one or more functions in an organic electronic device,including but not limited to, planarization of the underlying layer,charge transport and/or charge injection properties, scavenging ofimpurities such as oxygen or metal ions, and other aspects to facilitateor to improve the performance of the organic electronic device. Thebuffer layer is usually deposited onto substrates using a variety oftechniques well-known to those skilled in the art. Typical depositiontechniques, as discussed above, include vapor deposition, liquiddeposition (continuous and discontinuous techniques), and thermaltransfer.

An optional layer, not shown, may be present between the buffer layer120 and the electroactive layer 130. This layer may comprise holetransport materials. Examples of hole transport materials have beensummarized for example, in Kirk-Othmer Encyclopedia of ChemicalTechnology, Fourth Edition, Vol. 18, p. 837-860, 1996, by Y. Wang. Bothhole transporting molecules and polymers can be used. Commonly used holetransporting molecules include, but are not limited to:4,4′,4″-tris(N,N-diphenyl-amino)-triphenylamine (TDATA);4,4′,4″-tris(N-3-methylphenyl-N-phenyl-amino)-triphenylamine (MTDATA);N,N′-diphenyl-N,N′-bis(3-methylphenyl)-[1,1′-biphenyl]-4,4′-diamine(TPD); 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC);N,N′-bis(4-methylphenyl)-N,N′-bis(4-ethylphenyl)-[1,1′-(3,3′-dimethyl)biphenyl]-4,4′-diamine(ETPD); tetrakis-(3-methylphenyl)-N,N,N′,N′-2,5-phenylenediamine (PDA);α-phenyl-4-N,N-diphenylaminostyrene (TPS); p-(diethylamino)benzaldehydediphenylhydrazone (DEH); triphenylamine (TPA);bis[4-(N,N-diethylamino)-2-methylphenyl](4-methylphenyl)methane (MPMP);1-phenyl-3-[p-(diethylamino)styryl]-5-[p-(diethylamino)phenyl]pyrazoline(PPR or DEASP); 1,2-trans-bis(9H-carbazol-9-yl)cyclobutane (DCZB);N,N,N′,N′-tetrakis(4-methylphenyl)-(1,1′-biphenyl)-4,4′-diamine (TTB);N,N′-bis(naphthalen-1-yl)-N,N′-bis-(phenyl)benzidine (α-NPB); andporphyrinic compounds, such as copper phthalocyanine. Commonly used holetransporting polymers include, but are not limited to,polyvinylcarbazole, (phenylmethyl)polysilane, poly(dioxythiophenes),polyanilines, and polypyrroles. It is also possible to obtain holetransporting polymers by doping hole transporting molecules such asthose mentioned above into polymers such as polystyrene andpolycarbonate.

Depending upon the application of the device, the electroactive layer130 can be a light-emitting layer that is activated by an appliedvoltage (such as in a light-emitting diode or light-emittingelectrochemical cell), a layer of material that responds to radiantenergy and generates a signal with or without an applied bias voltage(such as in a photodetector). In one embodiment, the electroactivematerial is an organic electroluminescent (“EL”) material. Any ELmaterial can be used in the devices, including, but not limited to,small molecule organic fluorescent compounds, fluorescent andphosphorescent metal complexes, conjugated polymers, and mixturesthereof. Examples of fluorescent compounds include, but are not limitedto, pyrene, perylene, rubrene, coumarin, derivatives thereof, andmixtures thereof. Examples of metal complexes include, but are notlimited to, metal chelated oxinoid compounds, such astris(8-hydroxyquinolato)aluminum (Alq3); cyclometalated iridium andplatinum electroluminescent compounds, such as complexes of iridium withphenylpyridine, phenylquinoline, or phenylpyrimidine ligands asdisclosed in Petrov et al., U.S. Pat. No. 6,670,645 and Published PCTApplications WO 03/063555 and WO 2004/016710, and organometalliccomplexes described in, for example, Published PCT Applications WO03/008424, WO 03/091688, and WO 03/040257, and mixtures thereof.Electroluminescent emissive layers comprising a charge carrying hostmaterial and a metal complex have been described by Thompson et al., inU.S. Pat. No. 6,303,238, and by Burrows and Thompson in published PCTapplications WO 00/70655 and WO 01/41512. Examples of conjugatedpolymers include, but are not limited to poly(phenylenevinylenes),polyfluorenes, poly(spirobifluorenes), polythiophenes,poly(p-phenylenes), copolymers thereof, and mixtures thereof.

Optional layer 140 can function both to facilitate electroninjection/transport, and can also serve as a confinement layer toprevent quenching reactions at layer interfaces. More specifically,layer 140 may promote electron mobility and reduce the likelihood of aquenching reaction if layers 130 and 150 would otherwise be in directcontact. Examples of materials for optional layer 140 include, but arenot limited to, metal chelated oxinoid compounds, such asbis(2-methyl-8-quinolinolato)(para-phenyl-phenolato)aluminum(III) (BAIQ)and tris(8-hydroxyquinolato)aluminum (Alq₃);tetrakis(8-hydroxyquinolinato)zirconium; azole compounds such as2-(4-biphenylyl)-5-(4-t-butylphenyl)-1,3,4-oxadiazole (PBD),3-(4-biphenylyl)-4-phenyl-5-(4-t-butylphenyl)-1,2,4-triazole (TAZ), and1,3,5-tri(phenyl-2-benzimidazole)benzene (TPBI); quinoxaline derivativessuch as 2,3-bis(4-fluorophenyl)quinoxaline; phenanthroline derivativessuch as 9,10-diphenylphenanthroline (DPA) and2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (DDPA); and any one ormore combinations thereof. Alternatively, optional layer 140 may beinorganic and comprise BaO, LiF, Li₂O, or the like.

The cathode layer 150 is an electrode that is particularly efficient forinjecting electrons or negative charge carriers. The cathode layer 150can be any metal or nonmetal having a lower work function than the firstelectrical contact layer (in this case, the anode layer 110). As usedherein, the term “lower work function” is intended to mean a materialhaving a work function no greater than about 4.4 eV. As used herein,“higher work function” is intended to mean a material having a workfunction of at least approximately 4.4 eV.

Materials for the cathode layer can be selected from alkali metals ofGroup 1 (e.g., Li, Na, K, Rb, Cs,), the Group 2 metals (e.g., Mg, Ca,Ba, or the like), the Group 12 metals, the lanthanides (e.g., Ce, Sm,Eu, or the like), and the actinides (e.g., Th, U, or the like).Materials such as aluminum, indium, yttrium, and combinations thereof,may also be used. Specific non-limiting examples of materials for thecathode layer 150 include, but are not limited to, barium, lithium,cerium, cesium, europium, rubidium, yttrium, magnesium, samarium, andalloys and combinations thereof.

The cathode layer 150 is usually formed by a chemical or physical vapordeposition process. In some embodiments, the cathode layer will bepatterned, as discussed above in reference to the anode layer 110.

Other layers in the device can be made of any materials which are knownto be useful in such layers upon consideration of the function to beserved by such layers.

In some embodiments, an encapsulation layer (not shown) is depositedover the contact layer 150 to prevent entry of undesirable components,such as water and oxygen, into the device 100. Such components can havea deleterious effect on the organic layer 130. In one embodiment, theencapsulation layer is a barrier layer or film. In one embodiment, theencapsulation layer is a glass lid.

Though not depicted, it is understood that the device 100 may compriseadditional layers. Other layers that are known in the art or otherwisemay be used. In addition, any of the above-described layers may comprisetwo or more sub-layers or may form a laminar structure. Alternatively,some or all of anode layer 110 the buffer layer 120, the electrontransport layer 140, cathode layer 150, and other layers may be treated,especially surface treated, to increase charge carrier transportefficiency or other physical properties of the devices. The choice ofmaterials for each of the component layers is preferably determined bybalancing the goals of providing a device with high device efficiencywith device operational lifetime considerations, fabrication time andcomplexity factors and other considerations appreciated by personsskilled in the art. It will be appreciated that determining optimalcomponents, component configurations, and compositional identities wouldbe routine to those of ordinary skill of in the art.

In one embodiment, the different layers have the following range ofthicknesses: anode 110, 500-5000 Å, in one embodiment 1000-2000 Å;buffer layer 120, 50-2000 Å, in one embodiment 200-1000 Å; photoactivelayer 130, 10-2000 Å, in one embodiment 100-1000 Å; optional electrontransport layer 140, 50-2000 Å, in one embodiment 100-1000 Å; cathode150, 200-10000 Å, in one embodiment 300-5000 Å. The location of theelectron-hole recombination zone in the device, and thus the emissionspectrum of the device, can be affected by the relative thickness ofeach layer. Thus the thickness of the electron-transport layer should bechosen so that the electron-hole recombination zone is in thelight-emitting layer. The desired ratio of layer thicknesses will dependon the exact nature of the materials used.

In operation, a voltage from an appropriate power supply (not depicted)is applied to the device 100. Current therefore passes across the layersof the device 100. Electrons enter the organic polymer layer, releasingphotons. In some OLEDs, called active matrix OLED displays, individualdeposits of photoactive organic films may be independently excited bythe passage of current, leading to individual pixels of light emission.In some OLEDs, called passive matrix OLED displays, deposits ofphotoactive organic films may be excited by rows and columns ofelectrical contact layers.

EXAMPLES

The concepts described herein will be further described in the followingexamples, which do not limit the scope of the invention described in theclaims.

Example 1

This example illustrates the preparation of a PFAP for determination ofthermal stability and for preparation of a thermally stable, conductivepolymer composition.

The polymer is a copolymer of 1,1-difluoroethylene (“VF₂”) and2-(1,1-difluoro-2-(trifluoromethyl)allyloxy)-1,1,2,2-tetrafluoroethanesulfonylfluoride (“PSEBVE”), which has been converted to the sulfonic acid form.The resulting polymer is referred to as Poly(VF₂-PSEBVE acid).

A 400 mL Hastelloy 0276 reaction vessel was charged with 160 mL ofVertrel® XF, 4 mL of a 20 wt. % solution of HFPO dimer peroxide inVertrel® XF, and 143 g of PSEBVE (0.42 mol). The vessel was cooled to−35° C., evacuated to −3 PSIG, and purged with nitrogen. Theevacuate/purge cycle was repeated two more times. To the vessel was thenadded 29 g VF₂ (0.45 mol). The vessel was heated to 28° C., whichincreased the pressure to 92 PSIG. The reaction temperature wasmaintained at 28° C. for 18 h. at which time the pressure had dropped to32 PSIG. The vessel was vented and the crude liquid material wasrecovered. The Vertrel® XF was removed in vacuo to afford 110 g ofdesired copolymer.

Conversion of the sulfonyl fluoride copolymer prepared above to sulfonicacid was carried out in the following manner. 20 g of dried polymer and5.0 g lithium carbonate were refluxed in 100 mL dry methanol for 12 h.The mixture was brought to room temperature and filtered to remove anyremaining solids. The methanol was removed in vacuo to isolate thelithium salt of the polymer. The lithium salt of the polymer was thendissolved in water and added with Amberlyst 15, a protonic acid exchangeresin which had been washed thoroughly with water until there was nocolor in the water. The mixture was stirred and filtered. Filtrate wasadded with fresh Amberlyst 15 resin and filtered again. The step wasrepeated two more times. Water was then removed from the final filtratesand the solids were then dried in a vacuum oven at about 60° C.

Comparative Example A

This comparative example illustrates the insufficient thermal stabilityof Poly(VF2-PSEBVE acid) made in Example 1.

The poly(VF2-PSEBVE acid) solid made in Example 1 was determined forthermal stability by thermal gravimetric analysis (TGA). It shows thatthe solid lost about 39% weight from 25° C. to 250° C., which revealsthat the acid polymer is not thermally stable.

A small amount of poly(VF2-PSEBVE acid) solid was dissolved in water toform a 2.4% solution. pH was measured to be 1.6. Ion chromatographyanalysis shows that the solution contains 0.7×10⁻⁶ g fluoride and98×10⁻⁶ g sulfate per one mL solution. The ion concentration isapproximately equivalent to <1×10⁻⁶ mole fluoride, and 1×10⁻⁶ molesulfate per one gram of the solution. Based on the solid % of thesolution and composition of poly[VF2(1 mole)-PSEBVE (1 mole) acid], thesolution contains about 59×10⁻⁶ sulfonic acid group per one gram of thesolution. The ion analysis data clearly shows that poly(VF2-PSEBVE acid)is in almost 100% protonic form. The protonic acid polymer whereexcessive proton is the source of poor thermal stability of thenon-perfluorosulfonic acid polymer, which becomes evident when comparedwith a perfluoro-polymeric sulfonic acid shown in Comparative Example 2.

Comparative Example B

This example illustrates the high thermal stability of Nafion®, aPoly(perfluoroethyleneethersulfonic acid) supplied by E.I. du Pont deNemours and Company, Wilmington, Del.

A 25% (w/w) aqueous colloidal dispersion of Nafion® having an EW of 1050was made using a procedure similar to the procedure in U.S. Pat. No.6,150,426, Example 1, Part 2, except that the temperature wasapproximately 270° C. The dispersion was dried into solids by flowingnitrogen at room temperature. It was determined for thermal stability byTGA. It lost about 4% weight from 25° C. to 300° C. in nitrogen. Theloss is primarily due to absorbed moisture because of hygroscopic natureof the acid polymer. The TGA shows that Nafion® in 100% protonic acidform is very stable. This is in marked contrast from poly(VF2-PSEBVEacid) solid, as illustrated in Comparative Example 1, which is not aperfluoropolymeric sulfonic acid.

Example 2

This example illustrates high temperature composition and stability ofhigh pH poly(VF2-PSEBVE acid).

Part of the dried solid made in comparative example 1 was dissolved inwater and added with NaOH/H2O solution to increase pH to 2.9. The pH2.9solution contains 2.4% (w/w) partially neutralized poly(VF2-PSEBVEacid). Ion chromatography analysis shows that the solution contains0.8×10⁻⁶ g fluoride, 113×10⁻⁶ g sulfate, and 1,320×10⁻⁶ g Na+ per one-mLsolution. The ion concentration is approximately equivalent to <1×10⁻⁶mole fluoride, 1.2×10⁻⁶ mole sulfate, and 57×10⁻⁶ g mole Na+ per onegram of the solution. Based on the solid % of the solution andcomposition of poly(VF2-PSEBVE acid), the solution contains about59×10⁻⁶ sulfonic acid group per one gram of the solution. The ion dataclearly reveals that only 7% of the sulfonic acid in poly(VF2-PSEBVEacid) remain as free acid.

Dried solid of the pH2.9 poly(VF2-PSEBVE acid) was determined forthermal stability by thermal gravimetric analysis (TGA). It lost only3.2% weight from 25° C. to 400° C. in nitrogen, The weight loss occurredat low temperature and was primarily due to absorbed moisture. The TGAresult clearly shows that sodium cations replacing some of the protonsin non-perfluoropolymeric acids enhances thermal stability of thepolymer. In this example, 93% of the protons were replaced with Na+.

Example 3

This example illustrates the preparation of thermally stable, andelectrically conductive polyaniline made in the presence ofPoly(VF2-PSEBVE acid).

78.61 g of deionized water and 45.38 g of 99.7% n-propanol were masseddirectly into a 1,000 mL reactor vessel at room temperature. Next,0.0952 mL (1.2 mmol) of 37% wt. HCl and 0.6333 mL (7.0 mmol) of aniline(distilled) were added to the reactor via pipet. The mixture was stirredoverhead with a U-shaped stir-rod set at 100 RPM. After five minutes,53.60 g of 4.39% water solution of the polymer (5.80 mmol) made inExample 1 (10.90 mmol) was added slowly via a glass funnel. The mixturewas allowed to homogenize at 200 rpm for an additional 10 minutes. 1.65g (7.2 mmol) of ammonium persulfate (99.99+%) dissolved in 20 g of DIwater was added drop wise to the reactants via syringe infusion pump insix hours. Eight minutes later the solution turned light turquoise. Thesolution progressed to being dark blue before turning very dark green.After the APS addition, the mixture was stirred for 60 minutes and 4.68g of Amberlyst®15 (Rohm and Haas Co., Philadelphia, Pa.) cation exchangeresin (rinsed multiple times with a 32% n-propanol/DI water mixture anddried under nitrogen) was added and the stirring commenced overnight at200 RPM. The next morning, the mixture was filtered through steel mesh.The pH of the Amberlyst® 15 treated dipsersion was 1.2. A portion of thedispersion was stirred with Amberjet® 4400 (OH) (Rohm and Haas Co.,Philadelphia, Pa.) anion exchange resin (rinsed multiple times with a32% n-propanol/DI water mixture and dried under nitrogen) until the pHhad changed from 1.2 to 5.7. The resin was again filtered off and thefiltrate is a stable dispersion. Solid % of the dispersion wasdetermined to be 1.85% (w/w).

Ion chromatography analysis shows that the dispersion contains 82.8×10⁻⁶g Na+, 315.8×10⁻⁶ g NH₄ ⁺, and 128×10⁻⁶ g sulfate per one mL of thedispersion. The ion concentration is approximately equivalent to17.5×10⁻⁶ mole (mmole) NH₄ ⁺, 3.6 mmole Na+, 1.3 mmole sulfate per onegram of the dispersion, respectively. Charge balance leaves 18.5 mmolesNH₄ ⁺ and Na+ available for association with sulfonic acid ofpoly(VF2-PSEBVE acid). Based on the solid %, and mole ratio ofpoly(VF2-PSEBVE acid) with respect to aniline used in thepolymerization, the dispersion contains about 36 mmole sulfonic acidgroup per one gram of the dispersion. UV/V is of the dispersion andsolid film reveals that the oxidation state of the polyaniline isderived from emeraldine base structure, therefore every two anilineshould have one sulfonic acid to form polyaniline emeraldine salt. Basedon the mole ratio of poly(VF2-PSEBVE acid)/aniline and solid %, thedispersion contains about 42 mmole aniline per one gram dispersion. Theamount aniline reveals that 21 mmole sulfonic acid per one-gramdispersion forms emeraline ammonium salt. Remaining free sulfonic acidin the poly(VF2-PSEBVE acid) is about 15 mmole per one gram of thedispersion. The free acids were less than the combined NH+ and Na+. Thisshows that there is no free acid left.

TGA shows that dried solid of Polyaniline/poly(VF2-PSEBVE acid) onlylost 7.5% from 25° C. to 400° C. in nitrogen. The weight loss occurredat low temperature and was primarily due to absorbed moisture. Thisexample clearly demonstrates that poly(VF2-PSEVE acid) forms thermallystable, electrically conducting polymer. Electrical conductivity of theconducting polymer is shown in Example 4.

Example 4

The examples illustrates the properties and device performance ofPolyaniline/Poly(VF2-PSEBVE acid).

The dispersion made in Example 3 was filtered through a 0.45 μmMillipore Millex®-HV syringe filter with PVDF membrane (Millex® is aregistered mark of Millipore Investment Holdings Ltd., Wilmington,Del.). The dispersions were spun onto glass at 1,000 RPM for 80 seconds,resulting in films having a thickness of 831 Å once baked at 130° C. for5 minutes in air and further baked at 200° C. for 10 minutes in glovebox. Conductivity was measured to be 4.0×10⁻⁴ S/cm.

The polyaniline/poly(VF2-PSEBVE acid) was then tested for deviceperformance. The dispersion was spun on a 6″×6″ glass plate. The platehad an ITO thickness of 100 to 150 nm and consisted of 16 backlightsubstrates. Each substrate consisted of 3 pieces of 5 mm×5 mm pixel and1 piece of 2 mm×2 mm pixel for light emission. The spin-coated films asbuffer layer layers were then baked at 130° C. for 5 minutes on a hotplate in air. The thickness of the baked buffer layers was about 80 nm.For light-emitting layer, a 1% (w/v) toluene solution of a greenpolyfluorene-based light-emitting polymer was spin-coated on top of thebuffer layer films and subsequently baked at 130° C. for 10 minutes on ahot plate in an inert atmosphere dry box. The thickness of the bakedfilms was 75 nm. Immediately after, a 3 nm thick barium layer and a350-400 nm aluminum layer were deposited on the green light-emittingpolymer films to serve as a cathode. The devices have efficiency of 10.5cd/A at 1,000 nits (cd/m²), voltage of 3.3 volt at 1,000 nits, andhalf-life of 500-600 hrs at 5,000 nits.

Example 5

This example illustrates the preparation of thermally stable,electrically conductive Poly(3,4-ethylenedioxythiophene) made in thepresence of Poly(VF2-PSEBVE acid).

42.59 g of aqueous solution of 2.89% Poly(VF₂—PSEBVE acid) made inExample 1 and 65.18 g deionized water were poured into a 250 mLErlenmeyer flask. The mixture was stirred with a magnetic stirrer for 10minutes. 0.101 mL (0.948 mmoles) of Baytron®-M (a trade name for3,4-ethylenedioxythiophene from H. C. Starck, Massachusetts, USA) wasadded to the reaction solution with stirring. The mixture was stirredfor 30 minutes. 2.99 g of the ferric sulfate stock solution made inExample 3 was then added to the reaction mixture and stirred for 2minutes. A sodium persulfate solution made with 0.28 g (2.04 mmoles)sodium persulfate (Fluka®, obtained from Sigma-Aldrich Corp., St. Louis,Mo., USA) and 9.11 g deionized water was dripped into the reactionmixture with a syringe pump in about 30 minutes. Polymerization wasallowed to proceed with stirring at about 23° C. for 23 and half anhour.

The reaction mixture was mixed with 2.63 g of Lewatit® S100 and 2.59 gof Lewatit® MP62® WS in the Erlenmeyer flask and stirred for 5 hours.The resulting slurry was then suction pre-filtered through a coarsefritted-glass funnel and then through a Buchner Funnel containing twopieces of Whatman #4 Filter Paper. Not only was filtration easy, butalso when finished there was no sedimentation on the Filter Paper. Yieldis 105.61 g. Solid % (w/w) of the dispersion was 0.95%. The pH of thedark filtrate was measured to be 4.3. Its dried (baked at 80° C. for 10minutes in vacuo) film conductivity was 5.8×10⁻⁴ S/cm.

The PEDOT/Poly(VF2-PSEBVE acid) dispersion made contains 0.95% solid andhas pH of 4.3. Ion chromatography analysis shows that the dispersioncontains 441×10⁻⁶ g Na⁺, 4.2×10⁻⁶ g NH₄ ⁺, 214×10⁻⁶ g per one mLdispersion. The ion concentration is approximately equivalent to 19×10⁻⁶mole Na⁺, 0.2×10⁻⁶ mole NH₄ ⁺, 2.2×10⁻⁶ mole sulfate per one gram of thedispersion. Charge balance leaves 15 mmoles NH₄ ⁺ and Na+ available forassociation with sulfonic acid of poly(VF2-PSEBVE acid). Based on thesolid %, and amount of poly(VF2-PSEBVE acid) used in the polymerization,the dispersion contains about 20.3×10⁻⁶ sulfonic acid group per one gramof the dispersion. This reveals that about 70% of the sulfonic acidgroup forms sodium and ammonium salt in the solid. Some of the remainingsulfonic acid anions form complexes with partially oxidized3,4-ethylenedioxythiophene (EDOT) to balance the positive charges. It isreasonably estimated that about 3.5 EDOT unit is one electron deficient.Total number of EDOT used in the polymerization is 1.8×10⁻⁶ mole pergram of the dispersion. It is therefore estimated that 1.8×10⁻⁶ sulfonicacid is used as anions to balance the partially oxidized poly(EDOT).This leads to about 17% of the sulfonic acid still remains as free acidin the solid.

TGA shows that dried solid of PEDOT/poly(VF2-PSEBVE acid) only lostabout 8% from 25° C. to 400° C. in nitrogen. The weight loss occurredmostly at low temperature and was primarily due to absorbed moisture.This example clearly demonstrates that poly(VF2-PSEVE acid) formsthermally stable, electrically conducting polymer.

Example 6

This example illustrates the use of the thermally stable, electricallyconductive polymer as a buffer layer in an electronic device. Theconductive polymer composition ispoly(3,4-ethylenedioxythiophene)/poly(VF2-PSEBVE acid) from Example 5.

The 0.95% (w/w) aqueous dispersion made in Example 5 was tested fordevice performance. The dispersion was spun on a 30 mm×30 mm ITO/glasssubstrate. The substrate had an ITO thickness of 100 to 150 nm andconsisted of 3 pieces of 5 mm×5 mm pixel and 1 piece of 2 mm×2 mm pixelfor light emission. The spin-coated films as buffer layer layers werethen baked at 90° C. in air for 30 minutes. The thickness of the bakedbuffer layers was 750 nm. For the light-emitting layer, a 1% (w/v)p-xylene solution of a green polyfluorene-based light-emitting polymerwas spin-coated on top of the buffer layer films and subsequently bakedat 90° C. in vacuum for 30 minutes. The final thickness was ˜750 Å.Immediately after, a 4 nm thick barium layer and a 200 nm aluminum layerwere deposited on the light-emitting polymer films to serve as acathode. The devices dropped from 2,000 nits to 1000 nits (half-life) in1200 hrs, which is a long stress-life at that luminance level.

Example 7

This example illustrates the preparation of a non-perfluorosulfonic acidpolymer for determination of thermal stability and for preparation of athermally stable, conductive polymer composition. The polymer is acopolymer of ethylene (“E”) and2-(2-(1,2,2-trifluorovinyloxy)-1,1,2,3,3,3-hexafluoropropoxy)-1,1,2,2-tetrafluoroethanesulfonylfluoride (“PSEPVE”), which has been converted to the sulfonic acid form.The resulting polymer is referred to as Poly(E-PSEPVE acid).

A 210 mL Hastelloy C276 reaction vessel was charged with 60 g of PSEPVE(0.13 mol) and 1 mL of a 0.17 M solution of HFPO dimer peroxide inVertrel® XF. The vessel was cooled to −35° C., evacuated to −3 PSIG, andpurged with nitrogen. The evacuate/purge cycle was repeated two moretimes. To the vessel was then added 20 g ethylene (0.71 mol) and anadditional 900 PSIG of nitrogen gas. The vessel was heated to 24° C.,which increased the pressure to 1400 PSIG. The reaction temperature wasmaintained at 24° C. for 18 h. at which time the pressure had dropped to1350 PSIG. The vessel was vented and 61.4 g of crude material wasrecovered. 10 g of this material were dried at 85° C. and 20 milliTorrfor 10 h. to give 8.7 g of dried polymer.

Conversion of the sulfonyl fluoride copolymer prepared above to sulfonicacid was carried out in the following manner. A mixture of 19.6 g ofdried polymer and 5.6 g lithium carbonate were refluxed in 300 mL drymethanol for 6 h. The mixture was brought to room temperature andfiltered to remove any remaining solids. The methanol was removed invacuo to afford 15.7 g of the lithium salt of the polymer. The lithiumsalt of the polymer was then dissolved in water and added withAmberlyst® 15, a protonic acid exchange resin which had been washedthoroughly with water until there was no color in the water. The mixturewas stirred and filtered. Filtrate was added with fresh Amberlyst® 15resin and filtered again. The step was repeated two more times. Waterwas then removed from the final filtrates and the solids were then driedin a vacuum oven at ˜60° C.

Comparative Example C

This comparative example illustrates insufficient thermal stability ofPoly(E-PSEPVE acid) made in Example 7:

The poly(E-PSEPVE acid) solid made in Example 7 was determined forthermal stability by thermal gravimetric analysis (TGA). It shows thatthe solid lost about 45% weight from 25° C. to 250° C., which revealsthat the polymer is not thermally stable.

A small amount of poly(E-PSEPVE acid) solid was dissolved in water toform a 1.82% solution. pH was measured to be 1.9. Ion chromatographyanalysis shows that the solution contains 21×10⁻⁶ g Li+, 8×10⁻⁶ g Na+,and 13.4×10⁻⁶ g sulfate per one mL of the solution. The ionconcentration is approximately equivalent to 3×10⁻⁶ mole Li+, 0.3×1×10⁻⁶mole Na+, and 0.1×10⁻⁶ mole per one gram of the solution. Based on thesolid % of the solution and composition of poly[E (1 mole)-PSEPVE (1mole) acid], the solution contains about 38.5×10⁻⁶ mole sulfonic acidgroup per one gram of the solution. The ion analysis data clearly showsthat poly(E-PSEPVE acid) is in almost 91% protonic form. The protonicacid polymer where excessive proton is the source of poor thermalstability of the non-perfluorosulfonic acid polymer, which becomesevident when compared with a perfluoro-polymeric sulfonic acid shown inComparative Example 2.

Example 8

This example illustrates high temperature composition of pH 3.0poly(E-PSEPVE acid).

A small amount of the dried solid made in Example 7 was dissolved inwater and added with NaOH/H2O solution to increase pH to 3.0. The pH 3.0solution contains 1.6% (w/w) partially neutralized poly(E-PSEPVE acid).Ion chromatography analysis shows that the solution contains 515×10⁻⁶ gNa+, 17.2×10⁻⁶ g Li+, and 15×10⁻⁶ g sulfate per one mL solution. The ionconcentration is approximately equivalent to 22.4×10⁻⁶ mole Na+ 2.5×10⁻⁶mole Li, and 0.2×10⁻⁶ mole sulfate per one gram of the solution. Basedon the solid % of the solution and composition of poly(E-PSEPVE acid),the solution contains about 34×10⁻⁶ sulfonic acid group per one gram ofthe solution. The ion data clearly reveals that only 28% of the sulfonicacid in poly(E-PSEPVE acid) remain as free acid.

Dried solid of the pH 3.0 poly(E-PSEPVE acid) was determined for thermalstability by thermal gravimetric analysis (TGA). It lost only 9% weightfrom 25° C. to 300° C. in nitrogen, The weight loss occurred at lowtemperature and was primarily due to absorbed moisture. The TGA resultclearly shows that sodium cations replacing some of the protons innon-perfluoropolymeric acids enhances thermal stability of the polymer.In this example, 72% of the protons were replaced with Na+.

Example 9

This example illustrates high temperature composition of pH 4.2poly(E-PSEPVE acid).

A small amount of the dried solid made in Example 7 was dissolved inwater and added with NaOH/H2O solution to increase pH to 4.2. The pH 4.2solution contains 1.8% (w/w) partially neutralized poly(E-PSEPVE acid).Ion chromatography analysis shows that the solution contains 663×10⁻⁶ gNa+, 19×10⁻⁶ g Li+, and 15×10⁻⁶ g sulfate per one-mL solution. The ionconcentration is approximately equivalent to 29×10⁻⁶ mole Na+ 2.8×10⁻⁶mole Li, and 0.2×10⁻⁶ mole sulfate per one gram of the solution. Basedon the solid % of the solution and composition of poly(E-PSEPVE acid),the solution contains about 38×10⁻⁶ sulfonic acid group per one gram ofthe solution. The ion data clearly reveals that only 17% of the sulfonicacid in poly(E-PSEPVE acid) remains as free acid.

Dried solid of the pH 4.2 poly(E-PSEPVE acid) was determined for thermalstability by thermal gravimetric analysis (TGA). It lost only 2% weightfrom 25° C. to 300° C. in nitrogen. The weight loss occurred at lowtemperature and was primarily due to absorbed moisture. The TGA resultclearly shows that sodium cations replacing some of the protons innon-perfluoropolymeric acids enhances thermal stability of the polymer.In this example, 83% of the protons were replaced with Na+.

Note that not all of the activities described above in the generaldescription or the examples are required, that a portion of a specificactivity may not be required, and that one or more further activitiesmay be performed in addition to those described. Still further, theorder in which activities are listed are not necessarily the order inwhich they are performed.

In the foregoing specification, the concepts have been described withreference to specific embodiments. However, one of ordinary skill in theart appreciates that various modifications and changes can be madewithout departing from the scope of the invention as set forth in theclaims below. Accordingly, the specification and figures are to beregarded in an illustrative rather than a restrictive sense, and allsuch modifications are intended to be included within the scope ofinvention.

Benefits, other advantages, and solutions to problems have beendescribed above with regard to specific embodiments. However, thebenefits, advantages, solutions to problems, and any feature(s) that maycause any benefit, advantage, or solution to occur or become morepronounced are not to be construed as a critical, required, or essentialfeature of any or all the claims.

In some embodiments, the invention herein can be construed as excludingany element or process step that does not materially affect the basicand novel characteristics of the composition or process. Additionally,in some embodiments, the invention can be construed as excluding anyelement or process step not specified herein.

The use of numerical values in the various ranges specified herein isstated as approximations as though the minimum and maximum values withinthe stated ranges were both being preceded by the word “about.” In thismanner slight variations above and below the stated ranges can be usedto achieve substantially the same results as values within the ranges.Also, the disclosure of these ranges is intended as a continuous rangeincluding every value between the minimum and maximum average valuesincluding fractional values that can result when some of components ofone value are mixed with those of different value. Moreover, whenbroader and narrower ranges are disclosed, it is within thecontemplation of this invention to match a minimum value from one rangewith a maximum value from another range and vice versa.

It is to be appreciated that certain features are, for clarity,described herein in the context of separate embodiments, may also beprovided in combination in a single embodiment. Conversely, variousfeatures that are, for brevity, described in the context of a singleembodiment, may also be provided separately or in any subcombination.

1. An electrically conductive polymer composition consisting of anelectrically conductive polymer formed from at least one precursormonomer selected from the group consisting of thiophenes, selenophenes,and tellurophenes, and a partially-fluorinated water-soluble acidpolymer, wherein at least 50% of acid protons on thepartially-fluorinated acid polymer are replaced with cations selectedfrom the group consisting of inorganic cations, organic cations, andcombinations thereof.
 2. The conductive composition of claim 1 whereinthe thiophene, selenophene and tellurophene precursor monomers compriseFormula I or Formula I(a) below:

wherein: Q is selected from the group consisting of S, Se, and Te; R¹ isindependently selected so as to be the same or different at eachoccurrence and is selected from hydrogen, alkyl, alkenyl, alkoxy,alkanoyl, alkythio, aryloxy, alkylthioalkyl, alkylaryl, arylalkyl,amino, alkylamino, dialkylamino, aryl, alkylsulfinyl, alkoxyalkyl,alkylsulfonyl, arylthio, arylsulfinyl, alkoxycarbonyl, arylsulfonyl,acrylic acid, phosphoric acid, phosphonic acid, halogen, nitro, cyano,hydroxyl, epoxy, silane, siloxane, alcohol, benzyl, carboxylate, ether,ether carboxylate, amidosulfonate, ether sulfonate, ester sulfonate, andurethane; or both R¹ groups together may form an alkylene or alkenylenechain completing a 3, 4, 5, 6, or 7-membered aromatic or alicyclic ring,which ring may optionally include one or more divalent nitrogen,selenium, tellurium, or oxygen atoms; and

wherein: Q is selected from the group consisting of S, Se, and Te; R⁷ isthe same or different at each occurrence and is selected from hydrogen,alkyl, heteroalkyl, alkenyl, heteroalkenyl, alcohol, amidosulfonate,benzyl, carboxylate, ether, ether carboxylate, ether sulfonate, estersulfonate, and urethane, with the proviso that at least one R⁷ is nothydrogen, and m is 2 or
 3. 3. The conductive composition of claim 2wherein, in the precursor monomer of Formula I, both R¹ together form—O—(CHY)_(m)—O—, where m is 2 or 3, and Y is the same or different ateach occurrence and is selected from hydrogen, halogen, alkyl, alcohol,amidosulfonate, benzyl, carboxylate, ether, ether carboxylate, ethersulfonate, ester sulfonate, and urethane, where the Y groups may bepartially or fully fluorinated.
 4. The conductive composition of claim 2wherein, in the precursor monomer of Formula I(a), m is two, one R⁷ isan alkyl group of more than 5 carbon atoms, and all other R⁷ arehydrogen, and the alkyl group may be partially or fully fluorinated. 5.The conductive composition of claim 1 wherein the partially-fluorinatedacid polymer comprises Formula XV:

where j≧0, k≧0 and 4≦(j+k)≦199, Q¹ and Q² are F or H, R_(f) ² is F or aperfluoroalkyl radical having 1-10 carbon atoms either unsubstituted orsubstituted by one or more ether oxygen atoms, h=0 or 1, i=0 to 3, andg=0 or
 1. 6. The conductive composition of claim 1 wherein thepartially-fluorinated acid polymer is dispersible in water.
 7. Theconductive composition of claim 1 wherein the partially-fluorinated acidpolymer is colloid-forming.
 8. The conductive composition of claim 1,wherein the conducting polymer is doped with the partially-fluorinatedacid polymer.
 9. The conductive composition of claim 1, wherein thecations are selected from the group consisting of ammonium ions,alkylammonium ions, sodium ions, potassium ions, partially oxidizedpolyaniline, and combinations thereof.
 10. A buffer compositioncomprising a conductive composition of claim
 1. 11. A buffer layercomprising a conductive composition of claim 1.